我正在使用 Apple 示例代码的这个示例：
http://developer.apple.com/iPhone/library/samplecode/TableSearch/index.html
在此示例中，UITableView 在启动时获取内容列表。点击 UISearchBar 并输入，内容列表将被过滤，同时检查 ScopeBar 的范围。
我必须将这种“即时搜索”重建为“普通搜索”：一开始我没有 TableView 的数据。用户应该点击 SearchBar，输入一些内容，按下“搜索”按钮，搜索请求将被发送到网络服务器。网络服务器的响应将被放入 TableView 中，用户可以切换范围以过滤结果集。更改 SearchBar 的值不会过滤结果列表。只有按下“搜索”才能发起搜索请求。
我拿了示例代码并重建它（底部的源代码）。但我有两个问题。
- 在 SearchViewController 的初始调用（使用 TabBar、SearchBar、ScopeBar、TableView）时，一切正常。有一个空的 TableView。但是，在 SearchBar 中单击并键入任何一个字符，都会显示一条消息，即“没有命中”。我怎么能避免呢？仅当用户按“搜索”并且确实没有匹配项时，才会出现此消息。
- 我的第二个问题：键入“hello”并按“Search”，TableView 没有列出结果。如果我单击“中止”或在不同的范围内，将列出结果。所以一定有像丢失的“重新加载”之类的东西？！
我希望有人能帮助我。非常感谢您的到来和最诚挚的问候。
我的源代码：
@implementation SearchViewController
@synthesize listContent, filteredListContent, savedSearchTerm, savedScopeButtonIndex, searchWasActive;
- (void)viewDidLoad {
// restore search settings if they were saved in didReceiveMemoryWarning.
if (self.savedSearchTerm) {
[self.searchDisplayController setActive:self.searchWasActive];
[self.searchDisplayController.searchBar setSelectedScopeButtonIndex:self.savedScopeButtonIndex];
[self.searchDisplayController.searchBar setText:savedSearchTerm];
self.savedSearchTerm = nil;
}
}
- (void)viewDidUnload {
// Save the state of the search UI so that it can be restored if the view is re-created.
self.searchWasActive = [self.searchDisplayController isActive];
self.savedSearchTerm = [self.searchDisplayController.searchBar text];
self.savedScopeButtonIndex = [self.searchDisplayController.searchBar selectedScopeButtonIndex];
self.filteredListContent = nil;
}
- (void)dealloc {
[listContent release];
[filteredListContent release];
[super dealloc];
}
- (void)setData {
self.listContent = [NSMutableArray arrayWithCapacity:3];
[self.listContent addObject:[SearchObjects itemWithType:@"AAA" name:@"Test1"]];
[self.listContent addObject:[SearchObjects itemWithType:@"BBB" name:@"Test2"]];
[self.listContent addObject:[SearchObjects itemWithType:@"BBB" name:@"Test3"]];
// create a filtered list
self.filteredListContent = [NSMutableArray arrayWithCapacity:[self.listContent count]];
[self.tableView reloadData];
self.tableView.scrollEnabled = YES;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
//If the requesting table view is the search display controller's table view, return the count of the filtered list, otherwise return the count of the main list.
if (tableView == self.searchDisplayController.searchResultsTableView) {
return [self.filteredListContent count];
} else {
return [self.listContent count];
}
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *kCellID = @"cellID";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:kCellID];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:kCellID] autorelease];
cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
}
/* If the requesting table view is the search display controller's table view, configure the cell using the filtered content, otherwise use the main list. */
SearchObjects *searchObject = nil;
if (tableView == self.searchDisplayController.searchResultsTableView) {
searchObject = [self.filteredListContent objectAtIndex:indexPath.row];
} else {
searchObject = [self.listContent objectAtIndex:indexPath.row];
}
cell.textLabel.text = searchObject.name;
return cell;
}
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
// HERE IS THE SOURCE CODE FOR PUSHING TO THE NEXT VIEW
}
- (void)searchBarSearchButtonClicked:(UISearchBar *)searchBar {
// DO SOME CALCULATIONS… AND THE setData METHOD IS CALLED
}
- (void)filterContentForSearchText:(NSString*)searchText scope:(NSString*)scope {
/* Update the filtered array based on the search text and scope. */
[self.filteredListContent removeAllObjects]; // First clear the filtered array.
/* Search the main list for whose type matches the scope (if selected) and whose name matches searchText; add items that match to the filtered array. */
for (SearchObjects *searchObject in listContent) {
if ([scope isEqualToString:@"All"] || [searchObject.type isEqualToString:scope]) {
NSComparisonResult result = [searchObject.name compare:searchText options:(NSCaseInsensitiveSearch|NSDiacriticInsensitiveSearch) range:NSMakeRange(0, [searchText length])];
if (result == NSOrderedSame) {
[self.filteredListContent addObject:searchObject];
}
}
}
}
- (void)filterContentForScope:(NSString*)scope {
/* Update the filtered array based on the search text and scope. */
[self.filteredListContent removeAllObjects]; // First clear the filtered array.
/* Search the main list for whose type matches the scope (if selected); add items that match to the filtered array. */
for (SearchObjects *searchObject in listContent) {
if ([scope isEqualToString:@"All"] || [searchObject.type isEqualToString:scope]) {
[self.filteredListContent addObject:searchObject];
}
}
}
- (BOOL)searchDisplayController:(UISearchDisplayController *)controller shouldReloadTableForSearchString:(NSString *)searchString {
[self filterContentForScope:[[self.searchDisplayController.searchBar scopeButtonTitles] objectAtIndex:[self.searchDisplayController.searchBar selectedScopeButtonIndex]]];
// Return YES to cause the search result table view to be reloaded.
return YES;
}
- (BOOL)searchDisplayController:(UISearchDisplayController *)controller shouldReloadTableForSearchScope:(NSInteger)searchOption {
[self filterContentForScope:[[self.searchDisplayController.searchBar scopeButtonTitles] objectAtIndex:searchOption]];
// Return YES to cause the search result table view to be reloaded.
return YES;
}
@end